def shuizhan(n,t):
    A = [[0]*k for k in range(1,n+2)]
    A[0][0] = t
    for i in range(n+1):
        for j in range(i+1):
            q = (A[i][j]-1)/2
            if q>0:
                A[i+1][j] += q
                A[i+1][j+1] += q
    ####计算>1 的个数
    res = 0
    for i in range(n+1):
        for j in range(i+1):
            if A[i][j]>=1:
                res += 1
    return res

n,t = map(int,input().split())
print(shuizhan(n,t))
